The present invention relates to a pressure control valve, in particular for the pressure fluid control in slip-controlled hydraulic brake systems.
Conventional pressure control valves for the flow control of fluids in slip-controlled hydraulic brake systems are in wide use.
Pressure control valves are known, such as described in patent application P 39 30 757.3 for example, which have a valve tappet guided in a valve housing acted upon by a compression spring. The valve tappet end remote from the compression spring is formed as a spherical closure cooperating with a valve seat in order to interrupt the pressure fluid connection between the fluid supply and return in a leak-free manner when the valve is in its closed position.
In order to diminish the occurrence of noise and particularly the solid-borne sound during the stroke movement of the valve tappet, axially extending recesses are arranged unsymmetrically around the periphery of the valve tappet which bring about a radial pressure force resultant depending on the rate of flow and thereby an attenuation of the vibration. To manufacture such a shaped valve tappet, however, additional sophisticated machining steps are required.
It is therefore an object of this invention to improve upon a pressure control valve of the type referred to in such a manner as to achieve a major reduction in noise during the valve control phase with simple cost-efficient means, while the operational reliability is safeguarded at the same time.